Geri Horner belts out a Spice Girls classic while working up a sweat in her home gym as she prepares for big reunion tour

She's set to join her fellow Spice Girls for an epic stadium tour this summer.

And Geri Horner revealed she is getting into shape ahead of the big reunion both physically and vocally after posting a video of herself working out to a Spice Girls classic on Thursday morning.

The singer, 46, took to Instagram to upload a clip of herself working up a sweat on a step machine while singing hit song Spice Up Your Life.

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Spice Up Your Life: Geri Horner, 46, revealed she's getting into shape for the Spice Girls tour after posting an Instagram video of herself working out to a Spice Girls classic on Thursday

Dressed in black leggings, a black vest and black and white trainers, the mother-of-two showed off her svelte figure as she pumped her legs and arms in union while belting out the 1997 track.

Geri, who's married to Red Bull Formula One boss Christian Horner, 45, embraced her natural beauty by going make-up free for her exercise session, while her auburn tresses were tied back in a ponytail.